package com.zzz.test;

import com.sun.org.apache.bcel.internal.generic.NEW;
import com.sun.org.apache.regexp.internal.RE;
import io.netty.util.Timeout;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.AbstractQueuedSynchronizer;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;

/**
 * @author zhuzhizun
 * @date 2021/8/6
 */
public class MyReentrantLock implements Lock ,java.io.Serializable{


    private static class Sync extends AbstractQueuedSynchronizer{

        @Override
        protected boolean tryAcquire(int acquires) {
            assert acquires ==1;
            if (compareAndSetState(0,1)){
                setExclusiveOwnerThread(Thread.currentThread());
                return  true;
            }
            return false;
        }

        @Override
        protected boolean tryRelease(int acquires) {
            assert acquires == 1;
            if (getState() == 0){
                throw new IllegalMonitorStateException();
            }
            setExclusiveOwnerThread(null);
            setState(0);
            return true;
        }


        @Override
        protected boolean isHeldExclusively() {
            return getState() == 1;
        }

        Condition newCondition(){
            return new ConditionObject();
        }

    }


    private final Sync sync = new Sync();


    @Override
    public void lock() {
        sync.acquire(1);
    }

    @Override
    public void lockInterruptibly() throws InterruptedException {
        sync.acquireInterruptibly(1);
    }

    @Override
    public boolean tryLock() {
        return sync.tryAcquire(1);
    }

    @Override
    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
        return sync.tryAcquireNanos(1,unit.toNanos(time));
    }

    @Override
    public void unlock() {
        sync.release(1);
    }

    @Override
    public Condition newCondition() {
        return sync.newCondition();
    }
}
